Preparation of tocopheral carboxylates or tocotrienyl esters by acid-catalyzed reaction with carboxylic acids
申请人:BASF Aktiengesellschaft
公开号:US06365758B1
公开(公告)日:2002-04-02
A process for preparing tocopheryl esters or tocotrienyl esters by acid-catalyzed esterification of a tocopherol or a tocotrienol in a solvent while stirring at elevated temperature, which comprises
a) carrying out the esterification with the appropriate carboxylic acid,
b) carrying out the esterification with from 2.5 to 6 mol of the carboxylic acid in an aliphatic, cycloaliphatic or aromatic hydrocarbon boiling in the range from 80 to 200° C.,
or else with from 1.0 to 2.5 mol of the carboxylic acid in a mixture consisting of an aliphatic or cycloaliphatic hydrocarbon boiling in the range from 80 to 200° C. and a cyclic carbonate of the formula II or a &ggr;-lactone of the formula III
where R1, R2 and R3 are each H or lower alkyl, and R4 is H, lower alkyl, phenyl or methoxymethyl, as solvent,
c) using a nonoxidizing strong inorganic or organic acid, preferably sulfuric acid, boroxalic acid or benzene- or toluenesulfonic acids, in catalytic amounts as acid catalyst, and
d) continuously removing the water formed in the reaction by azeotropic distillation during the reaction.
通过在溶剂中在高温搅拌的条件下,通过酸催化酯化α-生育酚或α-生育三烯酚制备生育酚酯或生育三烯酚酯的过程,包括a) 使用适当的羧酸进行酯化反应,b) 在沸点在80至200°C范围内的脂肪族、环脂族或芳香族烃中使用2.5至6摩尔的羧酸进行酯化反应,或者在沸点在80至200°C范围内的脂肪族或环脂族烃与II式环碳酸酯或III式γ-内酯的混合物中使用1.0至2.5摩尔的羧酸进行酯化反应,其中R1、R2和R3分别为H或较低烷基,R4为H、较低烷基、苯基或甲氧基甲基作为溶剂,c) 使用非氧化性强无机或有机酸,优选硫酸、硼酸或苯基-或甲苯磺酸,作为催化剂的酸性催化剂,d) 在反应过程中通过共沸蒸馏连续去除所形成的水。